I. Field of Invention
The present invention concerns a two-piece stent combination for supplying oxygenated blood retrogradely from the left ventricle to the myocardium via the coronary sinus. It has an arterializing stent, which directs blood from the left ventricle to the coronary sinus, and a restricting covered stent, which controls the amount of blood flowing from the coronary sinus into the right atrium and thereby directing blood retrogradely to the myocardium.
II. Description of Related Technology
Retrograde perfusion of the heart through the coronary sinus has long been known for treating end-stage heart disease. Previous methods, among others, have attempted to connect the aorta to the coronary sinus during open-heart surgery using a graft of the jugular vein, the internal mammary artery, or the carotid artery. Alternatively, an occlusion balloon has been used for a short period of time.
Nelson et al. (U.S. Pat. No. 5,824,071, 1998) discloses an apparatus and method for providing retrograde perfusion directly from the left ventricle to the coronary sinus. Although Nelson requires a pressure sensitive valve that prevents pressure build-up inside the coronary sinus from rising above 60 mm Hg, Nelson does not teach how such a valve may be constructed. Nelson does not teach or describe the features or components of such a pressure sensitive valve. Further, it is unlikely that such a device may be introduced percutaneously and will likely require invasive surgery.
In 2000, Patel et al. conducted an experiment for percutaneous arterialization of the coronary sinus using a stent. See Patel et al, Percutaneous Transmyocardial Intracardiac Retroperfusion Shunts: Technical Feasibility in a Canine Model, JVIR 2000, 11:382-390. The stent employed by Patel et al., however, results in a significant amount of shunting of oxygenated blood from the left ventricle to the right atrium (hereinafter “left-to-right shunt”). These shortcomings in the prior art are solved by the present invention.